It could either go out the unused walled in chimney that the oil furnace was vented through or they could cut a hole in the concrete block wall and vent it out the side of the house.
Venting gas furnace thru wall.
Direct venting or side wall vent chimney and flue systems are a method of venting the exhaust gases from a heating appliance directly out through the side wall of a building while eliminating the need for a vertical chimney of any sort.
When venting your gas furnace you need to know the different kinds of vents that can be installed.
A direct vent will directly throw all the air into the atmosphere.
The fix was to use double wall b vent with an external power venter.
The basement ceiling is about 6 1 2 or 7 feet high.
Most old gas furnaces use such a mechanism while modern furnaces use the b pipes.
Williams wall furnace propane wall heater 600 900 sq.
The dvag11l direct vent wall heater from ashley the dvag11l direct vent wall heater from ashley hearth products makes the perfect solution for zoned heating.
Not familiar with your specific furnace but there were literally thousands of 80 furnaces horizontally vented through sidewalls in the late 80s and 90s.